503.Which of the following statement is with respect to tertiary dentin

a.It can always be seen in routine intraoral radiographs.
b.Can be observed in demineralized histological sections
c.It is initially  termed as secondary dentine
d.Starts when the lesion starts in enamel carious lesions

Ans-b.Can be observed in demineralized histological sections

502.Wallenberg syndrome is due to the complete infarction of

a.Posterior inferior cerebellar artery
b.Anterior inferior cerebellar artery
c.posterior cerebral artery
d.spinal artery

Ans-a.Posterior inferior cerebellar artery

501.In Gypsum bonded investment,composition of alpha hemihydrate is

a.60-65%
b.30-35%
c.5-10%
d.85-90%

Ans-b.30-35%
Explanation-Composition of gypsum bonded investment is 
Silica-60-65%
Alpha hemihydrate-30-35%
Modifiers-5%